Polyembryony, Biology

Assignment Help:

Polyembryony

Presence of more than one embryo in a seed is termed polyembryony. The phenomenon, first discovered in orange seeds by Leeuwenhoek (1719), attracted considerable attention because of its potential for application in and horticulture. Polyembryony is broadly classified into simple and multiple, depending on whether the supernumerary arises in one or more embryo sacs in the ovule. Simple polyembryony may be sexual or asexual. In sexual polyembryony embryos may originate from the fertilized egg and synergids, or by budding or cleavage of the polyembryony cells or suspensor of the zygotic embryo.

Asexual embryos are produced within the embryo sac without fertilization. Embryos may also originate from diploid nucellar or integumentary cells of the ode and grow into the embryo sac. These embryos are termed adventive or sporophytic. Multiple polyembryonies involve production of accessory embryos from two or more embryo sacs in the same ovule. For example, in the sea Island cotton, Gossypium barbadense, fertilization of egg in one embryo sac stimulates the induction of embryo from an unfertilized egg in the adjacent embryo sac within the same ovule. Thus, diploid-haploid twin embryos are produced in the seed.


Related Discussions:- Polyembryony

What is diffusion, Diffusion is the spreading of substance molecules from a...

Diffusion is the spreading of substance molecules from a region where the substance is more concentrated to other region where it is less concentrated. For example, during the boil

Role of microorganism in fermentation foods, Normal 0 false f...

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

Develop a hypothesis relating to the amount, Develop a hypothesis relating ...

Develop a hypothesis relating to the amount of dissolved oxygen measured in the water sample and the number of fish observed in the body of water.

Explain the eating disorder not otherwise specified (ednos), Explain the Ea...

Explain the Eating Disorder Not Otherwise Specified (EDNOS)? Earlier, we emphasized that a diagnostic category for eating disorders that fail to meet full criteria for anorexia

Show the structure of the adult fern, Q. What is the structure of the adult...

Q. What is the structure of the adult fern within which cells undergoing meiosis can be found? In these plants meiosis takes place within structures known as sorus (plural, sor

Meiosis, Meiosis is the special type of cell division in which the numbers ...

Meiosis is the special type of cell division in which the numbers of chromosomes in daughter cell are reduced to half, as compared to parent cell. Occurrence: It takes place

Define oven - nutritional biochemistry, Define Oven - Nutritional Biochemis...

Define Oven - Nutritional Biochemistry? Oven is a general term used to describe a chamber or enclosed compartment for heating, baking, or roasting food, as in a stove, or for f

Cell Cycle. M-cdk , Cell cycle Urgent question?? please biology expert! it'...

Cell cycle Urgent question?? please biology expert! it''s for an exam? When M-Cdk gets attached to cyclin, it doesn''t just get activated. phosphate has to be added by an activatin

What do you mean by fixation?, What do we mean by fixation? Fixation is...

What do we mean by fixation? Fixation is the process of preserving internal and external structures of microorganisms.  It leads to the killing of microbial cells and their fir

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd